Re: solution
- To: mathgroup at smc.vnet.net
- Subject: [mg118277] Re: solution
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Wed, 20 Apr 2011 04:26:24 -0400 (EDT)
You need to provide starting values outside of the range {1, 100}
r1 = Union[Table[k /. FindRoot[
BesselJ[0, k] + k BesselJ[1, k] == 0, {k, n}],
{n, 1, 100}], SameTest -> (Abs[#1 - #2] < 10^-4 &)];
Length[r1]
33
r2 = Union[Table[k /. FindRoot[
BesselJ[0, k] + k BesselJ[1, k] == 0, {k, n*Pi}],
{n, 1, 100}], SameTest -> (Abs[#1 - #2] < 10^-4 &)];
Length[r2]
100
For more roots, use a larger max value for n.
Bob Hanlon
---- amelia Jackson <meli.jacson at gmail.com> wrote:
=============
Dear MathGroup,
I have a problem. I want to find solution:
r := Table[
k /. FindRoot[BesselJ[0, k] + k BesselJ[1, k] == 0, {k, n}], {n, 1, 100}]
but I get about 30 roots. I need about 100 or more.
I think that "step" "n" tend to Pi
Please for help...
--
Bob Hanlon